It is known to provide permanently installed abrasive blast rooms provided with an air circulation and abrasive removal system so that the spent abrasive from the blast hose is reclaimed and can be returned for use in the blast hose. In most of these conventional permanent type of blast room installations, the exhaust air, after removal of the abrasive, is exhausted to the atmosphere. Because it is almost impossible to remove all of the abrasive particles from the exhausted air, the blast room is located in a remote position away from all operating equipment which needs to be cleaned on a regular schedule.
With this type of permanent blast room installation, objects to be cleaned in the blast room must be transported from the location where they normally operate to the remotely located blast room and returned after cleaning. When the objects to be cleaned are used as vital operating parts of a larger system, such as the turbines of a large electric generating plant, the removal of the turbines and transportation to the blasting room and return results in the electric generating plant being out of operation for a considerable length of time and this results in a considerable cost because of the loss of revenue from the electric generating system not being operable for a considerable length of time.
Abrasive blast cleaning at a location close to the operation site would provide a considerable savings over the system where the parts are transported to the blast abrasive cleaning operation and then returned to the operation's site. However, currently available onsite abrasive cleaning systems produce large amounts of dust which can escape and contaminate the machinery operating nearby, increase the clean-up cost, and further complicate the regular maintenance operations. Contamination by abrasive particles of critical oil seals, bearings and motor windings during scheduled cleaning of certain parts can actually cause equipment failure and increase the number of unscheduled maintenance operations.